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SAIL TRIM
Even the best autopilot can be crippled by poor boat trim, and the rudder and deadband settings effect how
accurately the boat holds the heading.
The boat must be balanced on all points of sail and in all wind conditions for proper CPT operation.
This means that through the skipper's selection of sails, trim and heading, the boat should tend to maintain a
stable course without a significant amount of weather or lee helm. Reef and trim or head-off when wind and
sea conditions increase. The CPT is not recommended for racing.
The rudder dial manually sets the rudder response for one consistent response, there is no automatic response
for changing conditions.
When sailing, the boat should maintain adequate speed for effective rudder control; it must make enough
headway for steering to be effective. When wind and seas increase, and especially when running downwind,
quick rudder response becomes important; lowering the deadband and slightly raising the rudder control
helps with full keels, and increasing vessel speed or falling off will lessen the effect of following seas. Fin keels
may benefit from lowering the rudder setting due to increased speed and rudder efficiency. Always be aware of
the relative wind angle, and keep the boat on a course to prevent an accidental gibe. If the boat is in danger of
broaching, change heading or speed, reduce canvas, or put a competent helmsman at the wheel. Because of the
manual rudder and deadband controls, the CPT performs best when the boat is balanced for consistent
steering needs. If the wheel needs to be turned very little while going down the face of a swell, but then turned
wildly at the bottom or in gusts, the boat is not balanced for the conditions, and the pilot will not anticipate the
constantly changing steering needs.
A. Boat Balance
A balanced boat has very little or no helm, either weather or lee. A boat that is in trim and balanced does not
round up to windward at every gust. A boat with a heavy weather helm is one that has been poorly trimmed or
is carrying a poor selection of sails. The boat should be trimmed for consistent steering needs.
By spending time trimming the boat properly before engaging the CPT, you will place lower current demands
on your boat's electrical system, steer a straighter average course and create less wear-and-tear on both your
boat and your CPT. Practically any boat can be made to sail with a balanced helm for reasonable lengths of
time. You should strive for this as closely as possible before engaging the CPT.
B. Beating
Do not carry too much sail area and do not over-sheet the sails. This will create weather helm, excessive heel
and probably slow you down. If the boat has weather helm, ease the main sheet until the main is on the point
of luffing or just luffing slightly. If the boat still has significant weather helm, take in a reef on the main or slide
the traveler car to weather, while easing the sheet to put some twist in the main to allow the top of the sail to
luff. In heavy weather conditions where one sail will suffice, sail under jib alone.
In gusting conditions some boats, particularly fin keel/spade rudder boats and others with too much canvas
spread, will head up at every gust. The main should be sheeted loosely enough so that it luffs as soon as the
boat heads up. With some boats the main should be left luffing slightly when on course. This will allow the jib
to push the boat off, as drive from the main is lost. Maintain a course that will give the boat an adequate steady
speed and effective rudder control. The goal is to balance the boat, and eliminate the need to change the
steering with every gust, to keep the steering needs consistent.
C. Running
If running downwind with twin poled-out jibs: The jibs should be sheeted a little looser than would be
optimum so that if the boat tries to round up the leeward sail will spill air and the boat will return to course.
